Disney didn’t sell such dresses at the time, but Mr Mooney immediately realised that the company was missing an incredibly lucrative trick.

“I was standing in line with mothers and daughters, all dressed head to toe in princess regalia that they had made at home,” says Mr Mooney, 63.

“I said to a few of the mums ‘if Disney made official dresses like this would you buy them?’, and they all replied that they’d buy lots.

“So I rushed back to [Disney headquarters] in Burbank [Los Angeles], and we launched the Disney Princess series pretty quickly.”

Not only did Mr Mooney and his team introduce dresses based on those worn by Disney’s best-known female characters, they set to work on everything from books to lunchboxes, dolls, magazines, computer games, pyjamas, and tie-ups with food producers.

The idea was to start selling basically everything that female Disney fans, both young and old, might like to buy, all featuring one or more Disney princess.

“By the end of 2001 sales across the Disney Princess lines were something like $300m, and today it is more than $6bn a year,” he says.